There is known a cellular phone including a display casing formed with a display screen, and an operation casing arranged with multiple operation keys, wherein the display casing is rotatably held in a plane parallel to the display screen by the operation casing (for example, Patent documents 1 and 2). This sort of cellular phone is adapted, for example, such that the display screen is formed in a rectangular shape, and by rotating the display casing with respect to the operation casing, switching between a vertically long state in which a longer direction of the display screen is made vertical to provide a display and a horizontally long state in which a shorter direction of the display screen is made vertical to provide a display can be performed to use the phone.
This sort of cellular phone includes one that includes an antenna for receiving a TV broadcast wave transmitted from a TV station, and is adapted such that a TV broadcast can be watched by displaying TV images on the display screen on the basis of the TV broadcast wave and outputting various types of TV voice corresponding to the TV images. The TV images have an aspect ratio typically representing a horizontally long shape, so that by bringing the display screen into the horizontally long state, the TV images can be displayed in an excellent condition.
On the other hand, in a case where telephone conversation is made in response to a call from an opposite side telephone set, the cellular phone is used with the display screen being in the vertically long state. The typical cellular phone includes a transmitting microphone for inputting voice at one end part in a longer direction of the operation casing, and a receiver for outputting voice from the opposite side telephone set at one end part in a longer direction of the display casing. Accordingly, the cellular phone is adapted to enable the telephone conversation in an excellent condition with a mouth being brought close to the transmitting microphone and an ear being brought close to the receiver by bringing the display screen into the vertically long state and bringing a face close to the cellular phone.
Patent Document 1: Japanese Unexamined Patent Publication No. 2004-215180
Patent Document 2: Japanese Unexamined Patent Publication No. 2005-12344